Condensed Consolidated Statements of Income (USD $) In Thousands, except Per Share data	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Revenues:
Premiums	$ 8,849,376	$ 8,376,751	$ 17,615,667	$ 16,538,614
Services	343,509	132,702	678,451	265,722
Investment income	91,246	79,790	180,731	165,245
Total revenues	9,284,131	8,589,243	18,474,849	16,969,581
Operating expenses:
Benefits	7,269,768	6,869,096	14,614,522	13,686,478
Operating costs	1,192,405	1,093,690	2,448,248	2,154,547
Depreciation and amortization	67,781	64,381	133,890	123,240
Total operating expenses	8,529,954	8,027,167	17,196,660	15,964,265
Income from operations	754,177	562,076	1,278,189	1,005,316
Interest expense	27,663	26,222	54,891	52,536
Income before income taxes	726,514	535,854	1,223,298	952,780
Provision for income taxes	266,227	195,778	447,835	353,936
Net income	$ 460,287	$ 340,076	$ 775,463	$ 598,844
Basic earnings per common share	$ 2.76	$ 2.02	$ 4.64	$ 3.56
Diluted earnings per common share	$ 2.71	$ 2.00	$ 4.57	$ 3.52
Dividends declared per common share	$ 0.25	$ 0.00	$ 0.25	$ 0.00